Bartlesville Police and Fire Department said several residents and staff members from a group home were taken to the hospital Wednesday evening.
According to police, health professionals were at Jacquelyn House, a facility for people with intellectual disabilities located near 5100 Jacquelyn Lane, to give flu shots. Authorities said they believe insulin shots were given instead.
According to police, the person who administered shots was a pharmacist who has been in practice for 40 years.
"At some point, and we don't know how it happened yet, the vial that contained the flu vaccine was traded out for a vile containing what we believe to be insulin," said Bartlesville Police Chief Tracy Roles.
Police said ambulances transported 10 people - eight residents and two staff members - to the Jane Phillips Hospital.
"I can't say enough about how good of a job the fire department and the EMS staff did containing the situation, controlling the situation, and doing what they needed to do to put the patients in the best possible position for recovery," Roles said.
According to police, the first 911 call came in at 4:30 p.m. about an unresponsive person.
First responders said the initial person's blood sugar was extremely low, and while they were there, they noticed other people exhibiting similar symptoms.
"The person who administered what we believe is insulin is being very cooperative. Not being evasive or elusive at all. I'm so hopeful that means that this was just a terrible accident. The bigger hope is that all of the patients who are at the hospital make a full recovery,"
Jane Phillips Hospital said all patients have been treated and will soon be released.
"How that happened is certainly something that I'm interested in knowing," Roles said.